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PATTERN OF BUDDING 

 Oral zone (Pis. XI, XIX) 



The oral end of the float carries the protozooid (the primary gastrozooid) and ventrally five or more 

 groups of cormidia arranged in oblique rows. The youngest cormidium lies nearest the protozooid 

 (PI. XIX, fig. i). 



Previous authors have mentioned the complexity of budding in the oral zone cormidia, but I know 

 of no detailed analysis of their structure and development. In unrelaxed specimens, such analysis is 

 well-nigh impossible, but among the few mature specimens that I have handled, specimen number 25 

 from Lanzarote, which had been specially relaxed in magnesium chloride, showed after dissection that 



Text-fig. 18. Physalia physalis. Proximal part of basal branch A (see Text-fig. 17) to show bases of six branchlets 

 described in the text. Scars could be seen at the bases of 2, 3 and 4 from which tentacles have been lost. 



the pattern of budding is essentially the same as in the main zone, except that the first two groups of a 

 cormidium, and sometimes the lee-branches as well, appear to open separately into the pericystic 

 space. This multiplicity of openings makes it less easy to separate the oral cormidia from one another 

 for individual examination. Five cormidia can be distinguished with certainty (PI. XI, fig. 4), but my 

 analysis of specimen number 25 (Table 11) (based on a unique well-relaxed animal, the only one ever 

 examined) shows that most probably seven oral zone cormidia are present in fully grown Physalia. 

 This will have to be confirmed by examination of additional relaxed specimens. 



The whole oral zone appears to be somewhat reduced and growth is less profuse. None of the oral 

 cormidia of specimen Lanzarote 25 has a tripartite group 1 , and only two have a tripartite group 2 . With 

 the exception of cormidium 1, neither are lee branches present in group 2; on the other hand in group 

 1, oral branches occur more frequently in this group than in the main zone (cf. Tables 10 and 11). 



The gastrozooids of the oral zone are definitely gastrozooids, not palpons, but they seem to develop 

 slowly and in the early stages are not easily recognizable (PI. XI, figs 1-3). 



